Physics · NDA previous year questions

Two bodies of unequal masses are dropped from a tower. At any instant, they have equal

1. A.Momentum
2. B.Acceleration
3. C.Potential energy
4. D.Kinetic energy

The frequency (f), wavelength (λ) and speed (v) of a sound wave are related as

1. A.$f=v\lambda$
2. B.$\lambda =vf$
3. C.$f=\frac{\lambda }{v}$
4. D.$v=\lambda f$

The length of a simple pendulum is increased four times to its previous value while the mass is doubled. What is the ratio of the new and previous time period of the pendulum?

1. A.3:1
2. B.2:5
3. C.2:1
4. D.3:2

What happens when the sunlight travels through the Earth’s atmosphere?

1. A.The blue colour is scattered more compared to the red colour
2. B.The red colour is scattered more compared to the blue colour
3. C.Both the blue and the red colours are scattered equally
4. D.The blue colour is not scattered but the red colour is scattered the most

When a solid body is partially or completely immersed in a fluid, the fluid exerts an upward force on the body. The magnitude of the force is equal to 1.the mass of the body 2.the weight of the displaced fluid by the body Which of the above is/are correct?

1. A.1 only
2. B.2 only
3. C.Both 1 and 2
4. D.Neither 1 nor 2

If the length of a copper wire is increased by twice, then its resistivity will be

1. A.Doubled
2. B.Halved
3. C.Same
4. D.One-fourth

Which one of the following is dimensionless quantity?

1. A.Stress
2. B.Strain
3. C.Pressure
4. D.Force

A system that does NOT allow exchange of heat with its surrounding is called

1. A.Adiabatic system
2. B.Non-adiabatic system
3. C.Equilibrium system
4. D.Non-equilibrium system

A current through a horizontal power line flows in east to west direction. What will be the direction of magnetic field at a point directly below it when viewed from east end?

1. A.Clockwise in a plane perpendicular to the wire
2. B.Anti-clockwise in a plane perpendicular to the wire
3. C.Clockwise in a plane parallel to the wire
4. D.Anti-clockwise in a plane parallel to the wire

When a light ray passes through from air to water with a non-zero angle the ray will be

1. A.bending towards the normal
2. B.bending away from the normal
3. C.propagating in straight line
4. D.reflected towards the opposite direction

Which one of the following equations related to the motion of an object is NOT correct? (Symbols carry their usual meanings)

1. A.$s=ut+\frac{1}{2}a{t}^2$
2. B.$u=v-at$
3. C.$u^2-v^2=2as$
4. D.Distance traveled during the $n^{th}$ second $=u+\frac{1}{2}a(2n-1)$

Which one of the following statements is NOT correct?

1. A.An ammeter is always connected in series in the circuit to measure the current
2. B.A Voltmeter is always connected to parallel in a circuit to measure the voltage
3. C.A voltmeter has a high resistance and an ammeter has a low resistance
4. D.A voltmeter has a low resistance and an ammeter has a high resistance

If three resistors of 1 Ohm each connect in parallel to each other the resultant resistance is

1. A.1 Ohm
2. B.1/3 Ohm
3. C.3 Ohm
4. D.9 Ohm

We hear an echo due to

1. A.Refraction of sound waves
2. B.Reflection of sound waves
3. C.Diffraction of sound waves
4. D.Resonance due to sound waves

At uniform speed the acceleration is

1. A.Maximum
2. B.Minimum
3. C.Zero
4. D.Constant

The intermixing of particles of two different types of matter on their own is called

1. A.Osmosis
2. B.Brownian motion
3. C.Diffusion
4. D.Conductance

Two resistances of 5.0 Ω and 7.0 Ω are connected in series and the combination is connected in parallel with a resistance of 36.0 Ω. The equivalent resistance of the combination of three resistors is

1. A.24.0 Ω
2. B.12.0 Ω
3. C.9.0 Ω
4. D.6.0 Ω

1. A.${\rho }_2<{\rho }_{\mathrm{w}}<{\rho }_1$
2. B.${\rho }_2<{\rho }_1<{\rho }_{\mathrm{w}}$
3. C.${\rho }_1<{\rho }_2<{\rho }_{\mathrm{w}}$
4. D.${\rho }_1<{\rho }_{\mathrm{w}}<{\rho }_2$

Which of the following statements give characteristics of contact forces? 1. It appears between an object when it is in contact with some other object 2. It satisfies the third law of motion 3. It may appear between a pair of solid and fluid Select the answer using the code given below:

1. A.1 and 3 only
2. B.2 and 3 only
3. C.1 and 2 only
4. D.1, 2 and 3

Which one among the following figures correctly represents the ray diagram ? (Consider the lens to be thin)

1. A.Option 1
2. B.Option 2
3. C.Option 3
4. D.Option 4

Which one among the following diagrams may correctly represent the motion of a skydiver during a jump ?

1. A.Option 1
2. B.Option 2
3. C.Option 3
4. D.Option 4

For an electric circuit given below, the correct combination of voltage (V) and current (I) is

1. A.V = 900 V; I = 18 A
2. B.V = 300 V; I = 5.5 A
3. C.V = 600 V; I = 1 A
4. D.V = 300 V; I = 2 A

A point object is placed at the centre of curvature of a spherical concave mirror. Which one among the fol- lowing would be the correct location of image formed?

1. A.At infinity
2. B.At the centre of curvature
3. C.At the focal point
4. D.Between the focal point and the centre of curvature

A vehicle starts moving along a straight line path from rest. In first t seconds it moves with an acceleration of $2m/{\mathrm{s}}^2$ and then in next 10 seconds it moves with an acceleration of $5m/{\mathrm{s}}^2$. The total distance travelled by the vehicle is $550\mathrm{m}$. The value of time t is

1. A.$10\mathrm{s}$
2. B.$13\mathrm{s}$
3. C.$20\mathrm{s}$
4. D.$25\mathrm{s}$

A pumpkin weighs $7.5\mathrm{N}$. On sub- merging it completely in water, $\frac{3}{4}\mathrm{L}$ of water gets displaced. The acceleration due to gravity at the place where the pumpkin was weighed is $10m/{\mathrm{s}}^2$. Which one of the following is the correct value of the density of the pumpkin?

1. A.$10kg/{\mathrm{m}}^3$
2. B.$100kg/{\mathrm{m}}^3$
3. C.$1000kg/{\mathrm{m}}^3$
4. D.$10000kg/{\mathrm{m}}^3$